Olecranon Most Closely Correlates with Peak Growth Velocity
The olecranon is the anatomical structure that most closely correlates with peak growth velocity in adolescents.
Explanation of Growth Assessment Methods
During adolescent development, accurately determining skeletal maturity and peak growth velocity is crucial for managing conditions like scoliosis, where timing interventions relative to growth spurts is essential. Several anatomical markers can be used to assess skeletal maturity:
Olecranon Assessment
The olecranon method provides the most precise correlation with peak growth velocity, offering assessment in regular six-month intervals during the critical phase of peak height velocity 1. This method:
- Shows excellent concordance with the comprehensive Sauvegrain method (r = 0.977 for boys and r = 0.938 for girls)
- Demonstrates excellent interobserver reliability (r = 0.987 for boys and r = 0.992 for girls)
- Allows identification of five distinct developmental stages: two ossification nuclei, half-moon image, rectangular shape, beginning of fusion, and complete fusion
- Provides detailed evaluation of skeletal maturity prior to Risser grade 1
Triradiate Cartilage
While triradiate cartilage closure is an important developmental milestone, it occurs at approximately:
- 12 years of age in girls
- 14 years of age in boys
- This corresponds to the middle of the pubertal growth phase 1
- Triradiate cartilage closure coincides with the rectangular shape of the olecranon in 65% of boys and 61% of girls 1
Other Markers (Radius and Ulna)
While radius and ulnar markers are used in some skeletal age assessment systems, they don't correlate as precisely with peak growth velocity as the olecranon.
Clinical Significance
The correlation between olecranon development and peak growth velocity has important clinical applications:
Scoliosis Management: Prediction of the crankshaft phenomenon (progression of spinal curvature despite posterior fusion) is strongly associated with surgery performed before or during peak height velocity 2
Surgical Planning: In patients with open triradiate cartilages, surgery performed before or during peak height velocity is a strong predictor of the crankshaft phenomenon, while surgery during the deceleration phase typically avoids this complication 2
Acetabular Development: Acetabular version increases with advancing skeletal maturity, with significant changes occurring near physeal closure of the triradiate cartilage complex 3
Conclusion
The olecranon provides the most reliable and precise correlation with peak growth velocity, offering six-month interval assessments during the critical phase of adolescent growth. This makes it superior to other anatomical markers like the triradiate cartilage, radius, or ulna for precisely determining peak growth velocity.